RESUMO
PIP: The Bongaarts model quantifies intermediate variables that have a direct impact on fertility and it is related to the classical analytic framework of intermediate fertility variables (IFVs) introduced by Davis and Blake. The model requires data on age-specific proportions of women currently married, age-specific fertility rates (ASFRs), estimates of postpartum infecundability, and proportion of women currently using effective contraceptive methods. Horne, El-Khorazaty, and Suchindran (1990) developed a childbearing model estimating projected ages at 1st and last birth (AFB, ALB) and the reproductive life span (RLS), making use of only ASFRs available from either vital statistics or sample surveys. The correspondence between Bongaarts-type indices of marriage, contraception, and infecundability and the childbearing indices is discussed. Data on both fertility-inhibiting and childbearing indices were available for 225 subpopulations. Application 1: Characterization of the fertility-inhibiting indices by the childbearing indices. Contraceptive practice is the major fertility-inhibiting factor among women who stop childbearing before age 35 years, but for those women who stop reproducing in their late thirties, long duration of breastfeeding is. Application 2: Decomposition of fertility decline by the childbearing indices. For societies with a low TFR of only 2 births, contraceptive use plays the major role in achieving this low fertility level, regardless of age at 1st birth, and age at last birth not exceeding 35 years. Application 3: Annual fertility-inhibiting indices using ASFRs. In Kuwait the TFR declined from 4.7 births in the early 1960s to well below 2 births in the late 1970s and 1980s owing to direct government support to family planning programs. The correspondence model, using only macro-level vital statistics data, can predict indirectly fertility-inhibiting indices on an annual basis for countries lacking the micro-level data necessary for estimating those indices directly.^ieng